Refining system



A. G. PETERKIN, JR-

REFINING SYSTEM Filed April 8, 1926 5 mwczw INV NTOR.

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April 1, 1930.

Patented Apr. 1, 1930 UNITED- STATES PATENT OFFICE KLBEB'I. G.IPETERKIN, JB., BRYN HAWK, PENNSYLVANIA, ASSIGNOR TO THE AT- LANTICBEIINING COMIANY, 0F PHILADELPHIA, PENNSYLVANIA, .A. CORPORATION 03PENNSYLVANIA.

BEFINING SYSTEM Application filed April 8,

My invention relates to the art of refining hydrocarbon oils withparticular reference to a method of and apparatus for concurrentlyrefining and distilling an oil of the char- 5 acter aforesaid.

In accordance with my invention, vapors of a hydrocarbon oil duringtheir fractionation are brought into contact with a refining agent inmixture with hydrocarbon oil, and

more articularly, the last-mentioned oil is utiliza- 1e as a refluxingliquid.

Further in accordance with my invention, oil in vapor phase is passedalong a path into contacting relation with successive poo refluxingliquid maintained at successively lower temperatures, containing insuspension a solid refiningagent.

My invention is particularly applicable to the distillation ofhydrocarbon oil in the 2 manner described in Chillas Patent No.

1,612,572, December 28, 1926.

My invention resides in a method and apparatus of the characterhereinafter described and claimed.

For an understanding of my method, and for an illustration of some ofthe various forms my apparatus may take, reference is to be had to theaccompanying drawing, in

, which: 7

Fig. 1 is a schematic view of apparatus utilizable inaccordance with myinvention.

Fig. 2 is a fragmentary schematic view of a modification.

Fig. 3 is a schematic view of a modification ls of.

of the portion of the apparatus for feeding These fractions resultingfromfrom the column 1926. Serial No. 100,477.

and are subjected to refining processes of various natures by which suchdesirable results may be obtained as odor removal, color stabilization,sulphur removal, etc. Among the commonest refining methods are thetreatthe purpose ofremoving odoriferous compounds and rendering the lampoil sweet. The sulphuric acid treatment particularly produces in the oilpolymerized compounds of low volatility which interfere burning qualityof the oil. It is, therefore, common practice to re-distill the oilafterthese various chemical treatments.

I have found that oils may frequentl be refined in the course of theirnormal ractional distillation process by subjecting them in thefractionating column to the action of a solid refining agent introducedat some point held in suspension in the reflux liquid passing throughthe column, and flowing therewith countercurrent to the rising vapors inthe column. The solid reagent in the column,

used may be of various types \depending on the type of refining which isneeded. vFor example, for the removal of compounds tending to produce anunstable color in the condensed distillate I may use clay, fullersearth, bauxite, bone black, active carbons, and other equivalentcatalytic oradsorbent materials, hereinafter generically termed fullersearth. Where sweetening or sulphur removal is to be effected, I mayutilize a material, as copper oxide, lead oxide, mer curic oxide or thelike, hereinafter generical- 1y termed copper oxide, having the propertychemically combining with a sulphur compound or other undesired materialin the oil undergoing distillation. I may use one of these reagentsalone or a mixture of two or more of them in order to accomplish severaldifierent results at the same time.

In practicing my invention I prefer to use with the The solid reagentused in my method may superheated be fed in at the top of the column orat any point intermediate between the top of the column and the point ofvapor inflow. It is preferably introduced as a slurry mixed with aliquid similar to the reflux liquid. in the column at the point ofintroduction.

In the following description for purposes of description, it will beassumed that a midcontinent crude petroleum of about 35 P. I. gravity isbeing refined, although it shall be understood that my method isapplicable in connection with the refining of any hydrocarbon oil.

Referring to Fig. 1, the fractionating column A of any suitable type, asfor ere ample, equipped with the bubbler plates 1 in which are thedownfiow pipes 2 and the vapor uptakes 3 covered by the bubbler caps d,is utilized for the fractionation of the vanors or mixture of oil andvapors introduced rem any suitable heating structure, for example, apipe still, through the pipe 5. If desired, steam may be introducedthrough the pipe 6. The vapors in passing through the column arefractionated and the low boiling vapors are removed through the line 7,while unvaporized liquid and reflux are removed from the bottom of thecolumn. through the line 8, controlled by the valve 8". The vaporspassthrough the line 7 to the condenser B from which liquid passesthrough the line 9 to the water separator C. Water present in the oil oradded as steam is removed through the line 10 and discarded,

while oil passes through the line 11 to the flow box D where it isseparated into two streams, one of which passes through the line 12 to asuitable destination, as storage tank P and the other passing along linel3, thereafter serving as a reflux for the frac-- tlonating column.

The residue from the bottom of the column is passed through the line 8to the coolerE and thence to the storage tank P. As suitable elevationsin the column liquid drawotf lines 14, 15, 16 and 17 controlled,respectively, by valves 14, 15 16 and 17 are provided to effect theremoval of various intermediate cuts. In the example illustrated thesecuts are lamp oil distillate, gas oil, parafiine distillate and highviscosity distillate respectively. Naphtha vapors leave the top of thecolumn and the bottoms removed through the line 8 constitute asatisfactory asphalt.

In accordance with my invention, these various cuts are refined duringthe fractionation so that when passed to the storage tanks or otherdestinations, they will be substantially free from undesirable bodies.To this end, there is introduced into the column one or more solidrefinin agents which are caused to flow downwar ly with the reflux. Asillustrated, the solid reagent may be added to the reflux before thelatter is fed to the column or if desiredit may be introduced at anypoint below the introduction of reflux. In any event it is preferredthat the solid be fed to the column in suspension in a liquid havin acomposition similar-to that of the liquid in the column at the point ofintroduction. 7

That portion of the condensate to be used as reflux is forced by thepump F from line 13 to and through the line 18 to the tank G, from whichit may be fed continuously or in termittently by way of line 19controlled by valve 19 to the agitator H, to which the solid reagent,as, for example, a mixture of fullers earth and copper oxide in finelydivided condition is conducted from bin I along the chute 2O controlledby gate 21. In agitator H, the mixture is agitated by the propellormounted on the shaft 23 which may be actuated by pulley 2 L driven byany suitable mechanism, not shown. The m1 rture of naphtha and solidreagent passes under the action of pump J through the line 24% into thetop of the column A. and passes downwardly through the downilow pipes 2onto the plates 1 where it is brought into intimate contact with therising vapors.

The solid reagent reacts with the undesirable components of the liquidwith which it is brought into contact while passing through the column.In general, these undesirable constituents are the most reactiveconstituents, chemically, in the oil. They may he objectionable in thatowing to their reactivity they may oxidize readily to produce colorimparting bodies or may polymerize or oxidize with the formation ofresinous bodies or may produce corrosive effects upon the metalcontainers, etc. These various types of compounds are more readily actedupon by such solid reagents as are used in my process and may bechemically changed, due to the action of the solid reagent, to suchbodies as may be adsorbed by the solid or held in chemical combinationtherewith or may be converted into other compounds which are innocuous.

In ordinary fractional distillation substantial equilibrium isestablished between the vapor and the liquid on each plate by aninterchange of constituents whereby high boiling components of the vaporpass into the liquid phase while low boiling components of the liquidpass into the vapor phase. In fractional distillation in which thevapors are refined according to my invention, there is acontinualremoval from the liquid of the undesirable components by the action ofthe solid reagent. As similar undesirable materials are present in thevapor phase, there is a tendency to establish an equilibrium in respectto these components in the two phases. The resulfis that compounds passfrom the vap r phase into the llq ld cause of the greater ease offiltering to take theplace of those removed as a result of the action ofthe solid reagents. Thus in passage of the vapors upwardly through thecolumn there is a continual removal therefrom notonly 'of high boilingcomponents as in ordinary fractionation but also of those undesirableconstituents which react with the solid reagent passing downwardly insuspension in the reflux liquid.

Since the solid material passes through substantially the entire lengthof the column, the various fractions removed, as through drawofls 14,15, 16 and 17, contain some of this material in suspension. This solidmay be removed by settling or as shown by passing through the filters K,L, M, and N, of any suitable type, for example, rotary filters. Thefiltered fractions may then be passed through coolers R, S, T and U,from which they are led through the lines 25, 26,

v27 and 28 to suitable destinations, as the storage tanks P, P, P andP", respectively. In some cases it may be desirable to insert apreliminary cooler before the-filter. With the more viscous fractions itis desirable to filter at as high a temperature as possible bethe oil atelevated temperature.

In those cases where the residue withdrawn through the pipe 8 is ,ofsuch a nature that filtering is impractical to remove the solid reagent,the entire quantity of reflux may be withdrawn through the lowermostliquid drawofi' 17. The plate from which this drawoif leads is notprovided with a downflow pipe. This prevents the passage of any solidmaterial below the drawoif 17 and thus it is kept from mixing with theresidue.

An alternative method of carrying out my invention is to mix the solidreagent with the reflux liquid at some point below the top of the columnand cause ittoflow down through the column with the reflux liquid fromthis point. Referring to Fig. 2, there is illustrated one form ofapparatus suitable for carrying out this alternative method. By thismodification the entire reflux stream may be withdrawn from the columnat some particular point by causing the downflow pipe 2 of a plate 1 todischarge into the seal pan 29, supported, for example, by the rods 30from the plate 1 above. The reflux is withdrawn from seal pan 29 throughthe line 31 and is divided into two streams, one of which may be passedto storage and the other mixed with the solid reagent and returned tothe column. The division may be accomplished-by the use of the two pipes32 and 33 controlled, respectively, b the valves 32 and 33 or by a flowbox 'orot er means. The oil passing throu h the line 33 discharges intothe agitator into which extends the shaft 34 carrying the propeller 35,,Said shaft carrying the pulley 36 actuated by any suitable mechanism,not shown. Solid reagent the column should be modified as shown in Fig.3 wherein a trapped line 40 leads directly from the flow box D to thetop of the column.

When my manner last fect is. produced, for, since passes through. theseplates over which the suspension of solid reagent flows, it must allcome in contact with the liquid which is in contact with the refiningreagent and the objectionable constituents are changed or removed in thesame manner as inthe first application of my process described above.This alternative arrangement has an advantage in that the streamsremoved from the column above the point of introduction of the solidrefining reagent are not contaminated with the reagent and do not,therefore, require filtration. Furthermore these streams are free frompolymerized bodies produced by the catalytic action of the solidmaterial. In practicing this alternate invention is performed in thedescribed, the same refining efmethod, the solid reagent is mixed withthe all of the vapor, 3

reflux liquid preferably that which collects 1 which passes material tothe draw-off 16, this being the plate from which the second heaviestdistillate stream is removed. By following this procedure all of thesolid comes out with'the lowest stream on the palte and the variousother streams are not contaminated therewith The refining agents removedfrom the o l in the filters, K, L, M and N, may be revivified by anysuitable means and utilized for subse uent treatment of additionalquantities 0 oil. For example, the spent fullers earth and coppercompound may be roasted in any suitable furnace, thereby burning theadsorbed polymerized product from the former and oxidizing the latter tocopper oxide.

As a result of my invention, distillation of the oil into variousfractions and refining of these fractions are accomplished in one stepin the ordinary distillation apparatus without rehandling and with theuse of only a small amount'of extra equipment. effects a material savingover usual refin procedure in which it is necessary to conduct separateoperations involving separateagitators, stills, pumps, etc. There isalso a saving in fuel required, for, by refining during thedistillation, it is unnecessary to redistill the treated naphtha andlamp oil cuts as is done when they areacid treated. In effect, my.invention results in the refining of the -var-ious fractions without anyadditional cost over the, distillation other than that incident to theuse of the solid reagent.

The s stem herein described may be advantageous y utilized in or asapart of a system of the character described in Patent No. 1,7 09,87 4:,in which the petroleum charged through the pipe 5 into the column A ispreviously rapidly heated to high temperature in excess of the normalcracking temperature without substantial cracking; and in whichsuperheated steam is introduced into the column at or ad'acent thebottom thereof.

What I clalm is:

1. Apparatus for simultaneously fractionating and purifying vapors ofhydrocarbon oil comprising a fractionating column, means intermediatethe top and bottom of said column for withdrawing liquid fractionstherefrom, means for introducing into said column near its top liquidreflux oil, means for with drawing ata point between the top and hottomof said column a portion of said reflux oil, a bin containing solidpurifying agent, means for transferring puri ying agent rom said bininto mixture with a portion of said reflux oil withdrawn, and means forreturning the mixture to the column asreflux liquid.

2. A method for simultaneously fractionating and purifying the vapors ofhydrocarbon'oil, which comprises passing the vapors upwardly in contactand interchange relation with descending liquid reflux oil, removingliquid fractions of the oil from the fractionating zone, suspending asolid purifying agent in at least a portion of a fraction so removed,and passing the oil containing the suspended material in fractionatingrelation with at least a portion of the ascending vaors. Y

3. A method for simultaneousl fractionating and purifying the vapors 0hydrocarbon oil, which comprises passing the vapors upwardly in contactand interchange relation with descending liquid reflux oil having insuspension therein a solid purifyin agent, removing liquid fractions ofthe oil fiom the fractionating zone, and utilizing at least a portion ofone of the removed fractions as refluxing liquid by passing it infractionating relation to rising vapors in the fractionating zone.

4. A method for simultaneously fractionating and purifying the vapors ofhydrocarbon oil, which comprises passing the vapors upwardly in contactand interchange relation with descending liquid reflux oil havingfullers earth in suspension therein, remov ing liquid fractions of theoil from the fractionating zone, and utilizing at least a portion of oneof the removed fractions as reflux liquid by passing it in fractionatingrelation to rising vapors in the fractionating zone.

5. A method for simultaneously fractionating and purifying the vapors ofhydrocar- CERTIFICATE OF CORRECTION.

Patent No. 1,752,455. Granted April 1, 1930, to

ALBERT G. PETERKIN, JR.

It is hereby certified that error appears in the printed specificationof theabove numbered patent requiring correction as follows: Page 1,line 16, after the comma and before the word "containing" insert thewords "at least one of them", and line 94, before 'chemically" insertthe word "of"; page 2, line 42, strike out the article "a"; and thatth'esaid Letters Patent should be read with these corrections thereinthat the same may conform to the record of the case in the PatentOifiice.

Signed and sealed this 13th day of May, A. 1), I930.

M. J'. Moore, (Seal) Acting Commissioner of Patents.

